battery failure

[frankenstein]

i have now sufferd a second 6v battery failure in as many months on my goldflash....what battery do you all in the forum recommend.....ps thanks for all the advice on the spark plugs i took purchase and did 700 yards before vibes killed a cheap battery...carol nash recovery was great though....!...pic to

[LJ.]

tut tut... such a picture that we really don't want to see. Hope you get it sorted soon. 

[a101960]

I'm with Tombeau on this. Vibration is unlikely to be the cause of battery failure unless you have not cushioned it in the battery tray. Has the battery split? I think that maybe you should get the regulator checked out. If you are cooking the battery due to regulator problems then your dynamo will very soon be the next item to fail. I am not sure what it is that you are saying. Battery failure on an A10 should not immobilise it.

[groily]

Don't get it either.
Why did the engine stop/not work and require the breakdown truck? Has the magneto been swapped for some modern system?
A dead dynamo or battery in daylight should be a mere inconvenience.
Look forward to trying to understand whatever it is that actually happened.

[fido]

I have a gel filled sealed type battery on the A7. It is 12 volts using a 12 volt Morris Minor type mechanical reg box. It is due for a new battery but the present one was not new when I got it, from a chap who takes them out of fire alarms when they have reached half their expected life.

[octane]

Mmmmm; don't quite get how a battery can
collapse in 700 yards ?!

i have now sufferd a second 6v battery failure in as many months on my goldflash....what battery do you all in the forum recommend.

Now a days nice sealed 6V batteries for motorcycles are readily available. I'd go for that. The advantages are overwhelming.
No maintenance, no acid-spill, last longer, doesn't fail due to vibration. = no worries.

Bought this one for my A10:



Nice little gel 6V 12amp motorcycle battery.
 (Yeah I know; the book says to run a 13amp, but I've always used less-than-13amp batteries
with no problems... daylight-headlights-on and all)

[frankenstein]

hi folks....heres more details....the battery was not well cushioned....and the clamp holding it down just about did its job....the bike has electronic ignition..hence no battery power no spark,,,,the first battery failed whilst riding and the bike stopped dead...we shook the battery and it gave 4 volts then six then nothing after starting the engine and the vibes killed it....likewise the second battery failed whilst out on a run....we shook the battery and came on so we started the engine and same again the bike was dead....not to restart.....i have removed the battery and there was a smell of rotten eggs from it...yuk...i have order a varta...aka yuasa...but after reading the latest post a gel battery might have been better....does the dynamo current go to the battery first or to the voltage regulator as i suspect the voltage regulator might be duff...what voltage regulator does my bike use....your help in the forum is fantastic and any info is really appreciated..the ammeter shows a charge ok.....thats it for now!

[frankenstein]

i forgot to add..each battery lasted around one month and none of them split externally..p.s i had to ask the recovery guy what the most unreliable bike as far as his rescue recoverys go....and its not british bike...in fact he said it was rare to pick a bsa up....the most pick ups for him where bmws and hondas...quite a shock....in fact 25 bmws out of 55 pickups this month

[groily]

aha! That (the electronic ign) explains why you couldn't get home. Another lament for a lost magneto began to form in my head . . . but no matter.
Re where does the electrickery go . . .?  What gets to the battery is dictated by the behaviour of the regulator and cut-out. If you read the adjacent thread 'Points or Electronic Ignition' you'll get a few pointers. Whether you have an old-style mechanical regulator or a more modern electronic one, they all try to achieve the same thing - which is to feed enough juice into F to allow the dynamo to convert it into enough juice out of D to maintain the battery at the correct level of charge, regardless of load on it. If F is being overfed by a dodgy regulator, D will overfeed the battery until the dynamo gives up the struggle, after having overcharged or even boiled the battery. A fully-charged battery should not receive more than a small charge at normal running speeds. It'll show a discharge at low speed with all the lights on, and should balance to zero on the ammeter - guessing - at about 30-35mph in top gear. With electronic ignition, the load is greater to the tune of a  couple of amps probably. It is possible someone has tried to 'adjust' the regulator - if it's an old-style one - to up the output to cope with the ignition system. Bad plan for everything concerned.
Not sure whether you're at 6 or 12 volt. But with your ignition I'd say 12 was almost essential, and an electronic regulator much to be preferred. If I were you I'd think carefully about the idea of an Alton alternator to cope with the load, or think about sourcing a magneto. But it's very easy to spend other people's money and I guess in the meantime a decent battery - the biggest that you can get in the space given the risk of needing it to get you home when things stop working - plus a check on the dynamo input/output might reveal enough to get you over the immediate problem.

Lovely looking bike! Be good to hear when it goes as well as it looks. Best of luck and hope you can leave the breakdown truck for all those BMWs and Hondas from now on!

[fido]

Ah, this thread is turning out to demonstrate why most of us choose to stick with the magneto on these particular bikes. My A7 has a duff battery at the moment but I can still ride with lights as the dynamo and reg. box system is still doing it's job. If it had electronic ignition it would need a good battery for starting purposes as the dynamo won't do much at kickstarting type revs. I suppose the bigger the battery you use the less cushioning you can give it from vibration. A small sealed gel battery may be best, cocooned in foam rubber. You also need a good regulator. The mechanical ones can be adjusted for output voltage, as explained in Service Sheet 804 and 804A so you could adjust it for the slightly lower charge voltage required by the gel battery. It sounds like you are still on 6 volts which is just as well if you are running electronic ignition. On 12 volts you need to keep the revs higher to ensure a constant charge.
Re. the breakdown services, could it just be that there are more Hondas and BMWs on the road than other makes? 

[frankenstein]

hi folks..thanks for the swift answers...the bike was purchased with the electronic ignition so a mag might be an option one day...but not just now...i will replace the voltage regulator first..lucas rb108...and also the battery and hope we get somewhere...lets hope its not the dynamo

[groily]

unlikely to be the dynamo I reckon - if it's overcharging, it'll be the reg probably. Can recommend DVR2s, and have a couple of times. I've 2, one at 6v, one at 12v and both are excellent. Available from manortechnology for about 40 quid with whom I have no connection! Positive or negative earth - you're probably pos.